The Radiation and Free Radical Research Core (RFRRC) has been in operation since 1947, and became a developing HCCC core in 2000. The core progressed to a full HCCC-supported shared resource in 2005. It is directed by Dr. Douglas Spitz, who together with co-directors Drs. Frederick Domann, Garry Buettner, and Prabhat Goswami, oversees all core operations. All have considerable experience and international reputations in free radical-focused cancer research. The overall goal of the RFRRC is to provide state-of-the-art technologies to HCCC investigators doing both basic and translational studies, encompassing the roles of metabolic oxidative stress and redox signaling in cancer biology and therapy. The three basic services provided by this shared research resource are: 1) Ionizing radiation services, phosphorimaging, and cell-cycle analytical tools critical to understanding basic cellular behavior and responses to radiation and chemotherapy. 2) Electron paramagnetic resonance spectroscopy and other analytical chemistry detection methodologies for measuring free radicals, singlet oxygen, small molecule antioxidants, nitric oxide and the array of related oxidants and oxidative damage products. 3) Antioxidant enzyme services to provide easy access to technologies for modifying and measuring molecules responsible for pro-oxidant formation and oxidative damage. Major equipment available in the RFRRC includes several radiation sources, a Seahorse analyzer, various types of spectrophotometers, hypoxia chambers, and equipment for HPLC separation and analyte detection. The RFRRC provides HCCC members with easy access to specialized knowledge, reagents, equipment and resources in a highly collaborative and helpful environment. In the past calendar year, 40 HCCC members from all 4 Programs utilized this shared research resource. The long term goal of the RFRRC is to continue to facilitate research involving all aspects of redox cancer biology in the HCCC (and at other cancer centers nationally) for the purpose of developing novel analytic and therapeutic approaches, based on fundamental differences in oxidative metabolism in cancer cells.